The present invention relates to an integral skin polyurethane foam composition and a process for preparing said foam. In particular, the invention relates to those foams utilizing 1,1,1,2-tetrafluoroethane (HFC-134a) alone or as a co-blowing agent with water, which are useful in shoe sole applications. The use of HFC-134a and optionally water obviates the need to use the ozone depleting chlorofluorocarbons in polyurethane shoe sole systems.